How to get a guy to see your smart side?

This guy I am sort of having a fling with doesn't seem to know me beyond physical traits. He knows that I go to school as a business major and also work but I do not think he knows I am smart or prefer to have a more profound intellectual conversation with him... It is all just sexual. I know he thinks I am dumb because he sometimes uses excuses that are seriously so dumb the fact he would think I fall for them is seriously insane. It's kind of frustrating, but at the same time the way he communicates doesn't come off as "scholarly". I also understand that maybe that is how he wants to keep this relationship.. just fun and light but I would still want to show him my intellectual/smart side. Any suggestions on how to do this without coming off as a know-it-all and insane?